Pressure still header and assembling tool



Feb. 20, 1934. s. i-l. EDWARDS PRESSURE STILL HEADER AND ASSEMBLING TOOL Filed June 26. 1931 2 Sheets-Sheet l -illllll Invent y Allormy 5 Feb. 20, 1934.

S. H. EDWARDS PRESSURE STILL HEADER AND'ASSEMBLING TQOL Filed June 26; 1931 2 Sheets-Sheet 2 Inventor 7/ Q Wi /M v Patented Feb. 20, 5

' ;UNITE -(s rawsPATENT oFFicg,

to Standard Oil Company. of California; San Francisco, Calif a corporation of Delaware Application June 26, 1931.- Serial No. 547,006

I 6 Claims. (01. 81-57) This invention relates to return bends, or ing suflicient iorce to the screw holdingmeans headers, as they are commonly called, for meto make the compression joint between the tubing chanically 'joining and providing a fluid connec and .the header tight under the high pressures tion between the ends of two parallel tubes, or and temperatures under which theymay be used.

5 pipes. It is particularly adapted for use in water In accordance with the present invention, this Q0 tube boilers, oil stills, and similar apparatus in. difiic'ulty has been overcome by uniting the headwhich the tubes are numerous, are positioned er to the tubing with an elongated internally close together, and must withstand high working threaded nut provided with gear teeth around its pressures and temperatures. outercircu'mference, andthen devising a wrench lo An object of the invention is to provide a comprising a plurality of gears adapted to tlt header construction of desirable mechanical and about and engage with the teeth on the nut hydraulic characteristics, that-is, a header that whereby turning torque is applied to the nut is light, strong, heat resistant, and that has a at aplurality of points about its circumference. smooth internal bore at least as large as th By a suitable gear reduction, the wrench multilH bore f h u in it nne tsp v plies the power applied to the nut so that an et- Anether Object i to p v 8 h r th fective torque can be obtained of sufllcient magcan be readily attached and removed even when nitude to produce a leak proof joint. u d 011 tubes that are erowded y close It will be apparent that this type of connection gether. f V is not limited in its application to return bends 2c Another object is to provide aeheader that 'alone, but can also be used with elbows and can be readily and cheaply manulacturerl. other types of joints of that nature, where a Still-another object is to provide a wrench fitting is to be attached to a tube. that can be used to install, or remove, headers Referring to the drawings: H constructed in accordance. with my invention, Figy1 i a view partly-in cross section showing as Particularly w used 011 closely Spaced tubes, 9. pair of tubes united by a header in accords that can be operated eitherby manual or machine e with my invention. powe a d t is c p o exerting an extr me Fig. 2 is an end view or the header shown in lypoweriul-torque. Fig. 1. Present heedersend return bends 01 m Fig-3 is a'view' showing the wrench applied to 30 types, but those most generally used consist either a e 1 p 9 Of a heavy cast steel body'swaged to the tubes Fig. 4 is an end view 0! the wrench partlyin to be joined, or of flanged steel construction Section; adapted to be attached by numerous bolts Figs. 5 and 6 are sectional and end'views, refianges 011 the ends 01 the tubes- The first type spec'tively, of an element of the header construc- 35 is heavy and is only adapted to be made by tionshown i 1, eesting, which, with the 3 Steele required to Referring to Fig. 1, two adjacent parallel'tubes Prevent corrosion, is expensive to make, as the 1 are shown connected by a header 2. The open greater Prepertien 0f castings P is ends of header 2 are juxtaposed to the ends of feetive and u e releeted- FurthermFethe tubes 1, and may be sealed thereto by means of a so hydraulic eherectenstiw of headers of tms type gasket 3. The end of the header may be formed are usually P9 and e may cause large into a tongue 12, andthe end of pipe 1 may be pressure drop- In case. 11 to one tubei groovedto receive the tongue as shown, but this both tubes must Ilene-11y be cut burned construction is optional and flat surfaces may be f t header and both tubes are usually substituted. Various well-known forms of con- M stroyed during, the removing process. The flange t t faces requiring no gasket may also be seaf 1 type is u tis a t y chiefly b au e t is v The tubes 1, which may be of alloy steel, are v bul y. wh h p ve the close nesting f t upset, or thickened internally adjacent their ends tubes. r as shown at 4, and are provided withan outer A Simple expedlent to eliminate the lmSatiS- circumferential groove, or recess, 5 in which are so factory features of the headers described would fitted internally flanged steel retaining rings 6. 106 seem to be to provide a steel return bend adapted The rings '6 are split into two halves as shown in to be united to the ends of the tubes by some Figs. 5 and 6, so that they may be readily inserted sort oi screw connection. Heretolore, a serious in the grooves 5. Surroundin both ube 1 and impediment to the development of such a header split retaining ring 6, is an elongated cylindri- "i has been the lack of a suitable method of applycal steel nut 'l which has an inwardly projecting ll'o 10 of the header.

-7 to produce a tight joint, the outer flange 8 at one end forming a shoulder resting against the retaining ring 6. The upper internal portion of nut 7 is provided with screw threads 9 which cooperate with similar threads on the outer circumference of the end portion 10 of header 2.

The threads used to unite these parts may be of any desired type, but I have found the Acme form particularly The inner diameter of the portion of nut 7 immediately above the shoulder 8 is such as to fit snugly about the retaining ring 6 and prevent the shoulder 11 of the ring escaping from the groove 5 on the pipe 1. The header 2, nut 7, split ring 6, and tube 1 preferably should be constructed of similar metal in order that their coefiicient of expansion under temperature changes shall be the same. I have found a material known in the trade as KA2S chromium nickel iron alloy to be satisfactory for oil-still use. The header 2 may be forged in one piece or may be made from a return bend portion 41 of alloy steel electrically or autogenously welded as at 42 to a forged steel tubular section 43. Shoulders 26 having a bearing hole 25 are formed on the upper part of the header 2. Their use will be explained later.

In assembling the header, the nut 7 is first slipped over the end of pipe 1, then the two halves of the retaining ring 6 are inserted in the groove 5 and the nut 7 withdrawn toward the end of the tube as far as it will go, to hold the retaining rings .in position. The header 2 is then brought into position and the nut 7 threaded onto the shoulder By tightening the nut 7, the end 12 .of the header is brought firmly against the end of pipe 1 so that the joint is sealed against leakage. The efiiciency of a joint of this type depends, among other things, upon the force with which the two parts are held together. The force obtainable is usually limited by the torque which can be applied to the nut 7. To make possible the application of sufficient torque to nut circumference of nut 7 is made cylindrical in shape and is provided with gear teeth 13 (as shown to the best advantage in Fig. 2) to mesh with gears in a special wrench designed for use therewith.

' As shown in Fig. 3, this wrench consists of a frame comprising an upper plate 14 and a lower plate 15 united by a U-shaped joining wall 16. The lower plate 15 has a portion cut out forming an aperture 40, to permit it to slip over the end of the header 2 and fit snugly thereabout. Rotatably mounted between the plates 14 and 15 and equidistant from a central point, are a plurality of shafts 17. Theseshafts extend through bushings 18 in the upper plate 14 and through bushings 19 in the lower plate 15,

Shoulders 20 and 21 on the shafts bear against the ends of bushings 18 and 19 to prevent longitudinal motion of the shafts. Each shaft 17 has a pinion 28 with teeth formed therein adapted to mesh with the teeth on the nut 7 and the shafts .17 are positioned about nut 7 so that the teeth on each pinion 28 will mesh with the teeth 13. A driving shaft 22 is rotatably supported in a bushing 23 in the top plate 14, and, in use, is supported at its lower end by an extension 24 adapted to fit into bearing hole 25 in shoulder 26 on header 2. Mounted on shaft 22 between bushing 23 and the extension 24 is an elongated pinion 27 which meshes with a plurality of gears 38, each of which is mounted on and rigidly'attached to one of the shafts 17. To enable all thegears 38 to mesh with pinion 27, some of them are mountsuitable in this construction ed different distances from the plate 14, so that they overlap, as shown clearly in Fig. 3.

Fig. 4 shows how all the gears 38 mesh with the central pinion 27. The frame of the wrench is so dimensioned that driving shaft 22 is coaxial with nut 7, and the bearing 25, on header 2, is concentrically positioned with respect to the extended axis of nut 7; therefore, it follows that when the wrench assembly is dropped over the end of the header so that shaft extension 24 fits into bearing 25, the pinions 28 fit about the nut 7 and mesh with the teeth 13 thereon. In the tightening operation, a wrench may be applied to the hexagonal end 29 of driving shaft 22. and the shaft rotated.

The rotary motion of shaft 22 is transmitted through pinion 27 and gears 38 to shafts 17, forcing them all to rotate in the same direction, which causes pinion 28 on each shaft 17 to apply an equal turning moment to the nut 7. Obviously, bythe simultaneous application of force to the nut at a plurality of points around its circumference, far greater force can be exerted without injury thereto than if it were attempted to apply the total force at one point. In addition, the gear train provides a substantial multiplication of the force applied to shaft 22, since the pinion 27 on that shaft is of relatively small diameter compared with the diameter of gears 38 and the pinions 28 are of substantially smaller diameter than gears 38, and are usually smaller than the nut 7 with which they engage.

It will be noted that since there is an intermediate gear between shaft 22 and the nut 7, the direction of rotation of shaft 22 and of the nut 7 are the same, there being two reversals of direction; that is, clock-wise rotation of the shaft 22 produces counter-clockwise rotation of shafts 1'7 which in turn produce clockwise rotation of the nut 7'.

To protect workmen from possible injury, a light sheet metal guard 30 may be provided. It is attached to the upper plate 14 by screws 31 as will disclosed in Figure 3, and extends over the gears 38.

In utilizing the assembling wrench, a tube 1 is loosely attached to the header by giving the nut 7 a few turns by hand to hold the header roughly in position on the end of the tube. The wrench frame is then slipped over the header so that the centering pin 24 drops into the bearing hole 25 and the pinions 28 mesh with the teeth on the outer circumference of the nut 7. Shaft 22 is then turned either by applying a hand wrench to the hexagonal end 29 or by connecting, by any known mechanical means, a suitable source of rotary motion thereto. The rotation of shaft 22 rotates the gears 38 in the reverse direction and since the frame bearing the gears 38 is prevented from turning by the floor plate 15 which fits snugly about the header tube, the gears 38 and shafts 17 are forced to turn in bearings 18 and 19 and rotate the nut 7 by engagement between the teeth 13 on the nut and the teeth on pinions 28.

Obviously, to remove a header, the wrench is applied in the same manner and shaft 22 turned in the reverse direction. After the nuts 7 are the pinions 28 which engage with the nut may;

be made of relatively small diameter so that the wrench may be used on very closely spaced headers; thus in Fig. 3, the header 34 attached to an adjacent tube 32 is shown positioned just far enough away from the header 2 to permit clearance between the pinion 28 on shaft 17 and'teeth on the nut 33 of header 34.

Although I have shown a wrench capable of tightening only one of thenuts on a header at a time, it is possible to modify its construction to permit the simultaneous application of torque to both the nuts on a header. Various modifications of the gear and pinion combinations could also be developed, without departing from the essential features of the invention.

It should be noted that since the nut 7 screws ,onto the header 2, noundue tQrque or twisting strain is'applied to the tubes themselves; this is advantageous since such strains may tend to distort or injure the tubeseither at the time of assemblingthe headers or while they are under the stresses caused by high pressures or temperatures. v

I claim:

1. A wrench for turning a toothed union member on a pipe joint which is provided with a cen tering means, comprising a frame shaped to fit about said joint for preventing relative rotation 1 therebetween and having abearing member engaging with the centering means on said joint, a first gear'rotatably supportedin said frame and positioned to mesh with the teeth on said union ,member, a second gear ,attached to the first, a third gear rotatably supported in said frame and meshing with said second gear, and means for rotating said third gear.

2. A wrench for turning a toothed union memoer on a pipe joint which is provided'with a centering projection having a concentric surface,

comprising a frame shaped to fit about said joint for preventing relative rotation therebetween and having a bearing member fitting the concentric surface of the projection on the joint for centering said wrench with respect to said union member, a first gear shaft rotatably supported in said frame carrying a gear and positioned to mesh said gear with the teeth on said union member, a second gear fixed to said gear shaft and a third gear rotatably supported in said frame and meshing with said second gear and means for rotating said third gear.

3. An assembling tool for turning a toothed nut ona member of such configuration as to preclude the application of a socket wrench to the nut, said tool comprising a frame, a shaft supported in said frame, a pinion rigidly fixed on said shaft cut to mesh with the toothed nut, another gear fixed on said shaft larger than said pinion, a second shaft supported in said frame having a pinion meshing with the gear on said first shaft, and a projecting end on said'second shaft for connection to a source of rotary motion, said frame being shaped to fit about said member and prevent relative rotation therebetween.

4. A wrench for turning a toothed nut, comprising a frame, a plurality of shafts supported in said frame and having pinions attached thereto, said pinions being positioned to fit about and meshwith the toothed nut, a second, larger gear fixed to each of said shafts, a driving shaft supported in said'frame centrally with respect to said first shafts and a pinion on said driving shaft meshing with said larger gears on said first shafts.

5. A tool for turning a threaded nut on a return bend fitting, comprising a frame for enclosing the U of said. bend and rotatable actuating SAMUEL H. EDWARDS. 

